IMHO!
Starline is very good and reasonable. $49 per 500 rounds. Once fired I buy at the gun show, but, you have to careful, some cases look well used.
Here's a couple of sites to help you in your search.

I got great results from Scharch's processed .45 ACP brass. You still need to run it through the sizer die, but it's been deprimed and roll sized. It's about half of the price quoted by Starline; however, if you want virgin brass, you can't beat Starline.

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